阅读说明：本技术 一种深蓝发光聚合物及其制备方法 (Dark blue luminous polymer and preparation method thereof ) 是由 李建辉 于 2020-06-15 设计创作，主要内容包括：本发明属有机发光显示领域,特别涉及一种深蓝发光聚合物及其制备方法。本发明公开了一种深蓝发光聚合物,具有式(I)所示结构。本发明还提供了深蓝发光聚合物的制备方法,包括如下步骤：步骤1：氮气保护下,将2,7-二溴-9,9-二辛基芴,2,7-二(4,4,5,5-四甲基-1,3,2-二氧杂硼烷)-9,9-二辛基芴和2,7-二溴-2’,3’,6’,7’-四辛基-螺硅双芴进行Suzuki偶联反应得到式(II)所示聚合物；步骤2：将式(II)所示聚合物与N-(4-联苯基)-N-(4-溴苯基)-(9,9-二甲基芴基)胺通过Suzuki偶联反应制得式(I)所示聚合物。本发明解决了现有发光聚合物蓝光饱和度较低的技术问题。(The invention belongs to the field of organic light-emitting display, and particularly relates to a deep blue light-emitting polymer and a preparation method thereof. The invention discloses a deep blue luminescent polymer which has a structure shown in a formula (I). The invention also provides a preparation method of the deep blue luminescent polymer, which comprises the following steps: step 1: under the protection of nitrogen, carrying out Suzuki coupling reaction on 2, 7-dibromo-9, 9-dioctyl fluorene, 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spiro silicon bifluorene to obtain a polymer shown in a formula (II); step 2: and (3) carrying out Suzuki coupling reaction on the polymer shown in the formula (II) and N- (4-biphenyl) -N- (4-bromophenyl) - (9, 9-dimethylfluorenyl) amine to obtain the polymer shown in the formula (I). The invention solves the technical problem that the existing luminescent polymer has low blue light saturation.)

1. A deep blue light emitting polymer, characterized in that, its structural formula is shown in formula (I):

wherein n is 300-.

2. A preparation method of a deep blue luminescent polymer is characterized by comprising the following steps:

step 1: under the protection of nitrogen, carrying out Suzuki coupling reaction on 2, 7-dibromo-9, 9-dioctyl fluorene, 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spiro silicon bifluorene to obtain a polymer shown in a formula (II);

wherein n is 300-;

step 2: and (3) carrying out Suzuki coupling reaction on the polymer shown in the formula (II) and N- (4-biphenyl) -N- (4-bromophenyl) - (9, 9-dimethylfluorenyl) amine to obtain the polymer shown in the formula (I).

3. The method for preparing a deep blue light-emitting polymer according to claim 2, wherein the molar ratio of the 2, 7-dibromo-9, 9-dioctylfluorene, 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctylfluorene and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene in step 1 is 4:5: 1.

4. The method according to claim 2, wherein the molar ratio of the polymer represented by formula (II) to the N- (4-biphenyl) -N- (4-bromophenyl) - (9, 9-dimethylfluorenyl) amine in step 2 is 1: 2.

5. The method for preparing a deep blue light-emitting polymer according to claim 2, wherein the time of the Suzuki coupling reaction in step 1 is 12 hours.

6. The method for preparing a deep blue light-emitting polymer according to claim 2, wherein the temperature of the Suzuki coupling reaction in step 1 is 100 ℃.

7. The method for preparing a deep blue light-emitting polymer according to claim 2, wherein the time of the Suzuki coupling reaction in step 2 is 12-36 h.

8. The method for preparing a deep blue light-emitting polymer according to claim 7, wherein the time of the Suzuki coupling reaction in step 2 is 36 h.

9. The method for preparing a deep blue light-emitting polymer according to claim 2, wherein the temperature of the Suzuki coupling reaction in step 2 is 120 ℃.

Technical Field

The invention belongs to the field of organic light-emitting display, and particularly relates to a deep blue light-emitting polymer and a preparation method thereof.

Background

Since the first preparation of organic electroluminescent blue-light emitting diode (OLED) with a polyvinyl phenylene structure by 1990 Friend R.H. et al, the research on the hot tide of organic flat panel display materials and devices is initiated in the fields of material science and information technology. The blue light material has the lowest maturity, the fluorene polymer is taken as the main material to emit pure positive blue light at present, however, the poor spectral stability of the polyfluorene material is the most fatal weakness of the polyfluorene material, the emission wavelength of the polyfluorene blue light material can be red shifted and a green light emission band appears, so that the originally saturated deep blue light becomes green light or even yellow light, the chromatographic purity of the polyfluorene blue light material is seriously weakened, the application of the polyfluorene blue light material as the blue light polymer material is influenced, and the fluorescence quantum efficiency and the electroluminescent efficiency of the polyfluorene blue light material are also greatly reduced. Therefore, the low blue light saturation of the existing light-emitting polymers is a technical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention aims to provide a deep blue luminescent polymer.

The invention also aims to provide a preparation method of the deep blue luminescent polymer.

The purpose of the invention is realized by the following scheme:

the invention provides a deep blue luminescent polymer, which has a structural formula shown as a formula (I):

wherein n is 300-.

The invention also provides a preparation method of the deep blue luminescent polymer, which comprises the following steps:

step 1: under the protection of nitrogen, carrying out Suz uki coupling reaction on 2, 7-dibromo-9, 9-dioctyl fluorene, 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctyl fluorene and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene to obtain a polymer shown as a formula (II);

wherein n is 300-;

step 2: and (3) carrying out Suzuki coupling reaction on the polymer shown in the formula (II) and N- (4-biphenyl) -N- (4-bromophenyl) - (9, 9-dimethylfluorenyl) amine to obtain the polymer shown in the formula (I).

Preferably, the molar ratio of the 2, 7-dibromo-9, 9-dioctylfluorene, 2, 7-bis (4,4,5, 5-tetramethyl-1, 3, 2-dioxaborane) -9, 9-dioctylfluorene and 2, 7-dibromo-2 ', 3', 6', 7' -tetraoctyl-spirosilabifluorene in step 1 is 4:5: 1.

Preferably, in step 2, the molar ratio of the polymer shown in the formula (II) to the N- (4-biphenyl) -N- (4-bromophenyl) - (9, 9-dimethylfluorenyl) amine is 1: 2.

Preferably, the time of the Suzuki coupling reaction in the step 1 is 12 h.

Preferably, the temperature of the Suzuki coupling reaction in step 1 is 100 ℃.

Preferably, the time of the Suzuki coupling reaction in the step 2 is 12-36 h.

Preferably, the time of the Suzuki coupling reaction in the step 2 is 36 h.

Preferably, the temperature of the Suzuki coupling reaction in step 2 is 120 ℃.

Compared with the prior art, the invention has the following advantages and beneficial effects:

after the benzidine unit is introduced into the deep blue luminescent polymer prepared by the invention, the electroluminescence spectrum has obvious blue shift and narrowing, which shows that the color purity of the polymer prepared by the embodiment of the invention is obviously improved. And the device prepared from the dark blue luminescent polymer has the color coordinate blue shifted to the dark blue region of CIE (y is less than 0.1), which shows that the polymer prepared by the invention can emit dark blue light.

Drawings

FIG. 1 is an electroluminescence spectrum of deep blue light-emitting polymers obtained in examples 1 to 3 of the present invention and comparative example 1;

wherein the reference numerals

PFOSiT-36 for A, PFOSSiT-24 for B, PFOSSiT-12 for C, D: a polymer represented by the formula (II).

Detailed Description

The present invention will be described in further detail with reference to specific examples, which are not intended to limit the present invention in any manner. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.